Burr mill



"'iJul 6 ,1926

6. 5. CHAMBERLAHN BURR MILL Filed Nov. 25. 1921 sweets-sheet 1 Jul 6,1926, 1,591,919-

7 G. E CHAMBERLAIN sum MILL .Filed Nbv. 25. 1921. 5 Sheets-Sheet s.

. I A 55 1 J59 J g Patented Jul 6,1926.

UNI-TED STATES 1,591,919 PATENT OFFICE.

GEORGE E. cnmsnnnnn, ornnca'run, rumors; v

' I BURR MILL. I

Application filed November 25, 1921. Serial No. 517,474.

This invention relates to mills for grinding cereals of the type provided with upper and nether, stones revolving .one upon the other, and has for its object the provision of a grinding mill of the class named, which shall be of improved construction and operation. I

The invention is exemplified in the combination and arrangement of parts shown in the accompanying drawings and described inthe following specification, and it is more particularly pointed out in the ap-' pended claims.

In the drawings, Fig. 1 is a vertical sectional view, show ing one embodiment of the present invention.

Fig. 2 is a somewhat diagrammatic plan view showing a, detail of construction. Fig. 3 is a fragmentary vertical section show ng the driver for the upper stone.

Fig. 4 .is a section on line 4-4 of Fig. 3. Fig. 5 is a vertical section of the footstep bearings of the main drive shaft.

. parts of a drivingsupport for the upper stone.

In mills as heretofore constructed, having a revolving stone driven by a vertical shaft or spindle connected by belts or gearing with a sourceof power there has been considerable'loss of ower due to side pulls on the bearings an the arrangements have been lackingin economy and convenience of 35. floor space.

In the present invention a driving motor is mounted directly on the mill spindle, thus providing a more compact arrangement and avoidin the ing ball race 13' carried on a washer 14. A

[plate 15 rests one series of balls 16 travelmg on the race 13. A stud 17 is formed on the lower end of the millspindle 1 8 and the weight. of the spindle and supported parts is transmitted through a flange 19 on the shaft 18 to thesupporting balls 16. A series the motor. The cover plate 26 carries a cen- I 26laterally for adjusting the bearing for Figs. 6, -7 and 8 are perspective views of' is filled with cement, which firmly holds the friction loss due side pulls. vi '4 A sync ronous electric motor is preferably of balls 20 support the shaft-against lateral movement.

The frame 10 supports the pole pieces 21 forming the field of an electric motor, the armature of which is shownat 22 secured directly to the spindle 18. The coils 23 of the pole pieces are preferably made wider than usual to provide a field of sufiicient ex tent to permit vertical adjustment of the armature 22 without displacing it from the o5 field. Fan blades 23 may be carried by the armature 22 for the purpose of ventilation and cooling where desirable. Brushes 24 and slip rings 25 are provided for supply ing current to;the armat're 22. A cover plate .26 is supported on t eupper face of the motor field frame and completely shields the motor from any moisture which might fall fromthe' grinding stones or parts above trally disposed bearing 27 for the upper portion of the spindle. 18, and a series of screws 28 are provided for shifting the plate the upper end of the spindle. The frame 10 above the cover plate 26 carries a bed 29 having a circular side wall 30, in which the lower grinding stone 31'is supported. The stone 31 may be adjustably located on the bed 29 by screwsg32 extending upwardly through the bottom of the bed and laterally adjustable screws 33 projecting through the side wall 30. When the stone 31 has been accurately placed the space about the stone stone in place after it has set. The upper stone 35 is supported on the lspindle 18 by means .of a bail 36, shownmoreclearly in Figs. 3, 4 and '6. The bail 36 is rov1ded w th a tapered opening 37 in w ich the cockeye 3 8 is seated. Laterally projecting arms 39 engage recesses in the stone'3'5 for V supporting the stone. The ends of the arms 39 may be encased in bushings 40 to prevent injury to the stone. The cockeye, 38 is car- 00 ried by a ball and socket joint u on the cockhead 41,- which is provided wit a tapered seat in the supporting driver 42. The driver .42 fits over a reduced'portion 43 on the spindle 18 and is secured 'to the spindle 105 by .a pairof keys 44. Collars 45 are inter-' posed between .the lower end of the driver lowering of the driver on the spindle if the collars 45 are removed. This will allow for lowering of the upper stone on the spindle 18 as the faces of the stones wear away. The spindle itself is vertically adjustable, as will be explained, to provide for small vertical movements of the upper stone. Interposed between the supporting driver 42 and the bail 36 is an intermediate driver 47, Fig. 7, which is provided with arms 48 to engage openings 49 in the bail 36 and with openings 50 for receiving arms 51 on the supporting driver 42. In this way an efiicient means is provided for supporting the upper stone on' the spindle 18 so that the stone is driven by the rotation of the spindle and yet permitted a limited universal movement to accommodate the driving faces of the stones to one another.

Closely fitted packing 51 surrounds the lower portion of the supporting driver 42 and is contained in a circular box or gland 52 cemented or otherwise secured to the lower stone 31, as shown in Fig. 3. A metallic plate 53 covers the packing 51, and above the plate 53 is a wooden block 54 the upper face of which is flush with the upper face of the stone 51 and which wears away with the stone. This packing arrangement prevents moisture or other substance from leakin down about ,the shaft 18 to interfere with the shaft bearing or motor. A housin 55 surrounds the upper stone and is rovi ed with a hopper 56, through w ich grain is fed to the central opening in the uppzr stone from which it passes outwardly tween the stonesand is ground. A dischar e chute 57 is provided at one side of t e housing, and a sampling hand-hole 58 may be arranged above the chute 57 in the usual manner.

As shown in Figs. 1 and 2, the bearin support 12 isv rovided with a worm whee 59, which mes es with a worm 60 carried on the shaft 61. The shaft '61 is connected by beveled gearin 62 with a hand crank 63, b means of w oh the worm wheel 59 may rotated to or lower the spindle l8 and the up r stone 35. For more convenlent operation of the raising mechanism the shaft 61 is preferably provided with an electric motor 64 having a' etic :lutch 65 for connecting the motor wit the shaft. The clutch and motor are preferably arranged in series with one another in their electric circuit, so that when the circuit is closed for'operating the motor the clutch will automaticall connect the motor with the shaft and w enthe circuit is broken,

, hand wheel 63. The motor 64 is reversible and a control such as a pair of push buttons 1s provided by means of which it may from said grinder, an

be operated in either direction to any desired extent. This means provides a convenient device for adjusting the height of the stones relative to one another and for raising the upper stone in case the supply of grain to the mill is shut off or for any other reason that may occur in the operation of the mill.

I claim:

1. A mill havin a pair of grinders arranged one above t e other, a vertical spindle supporting one of said. grinders, means for raising and lowering said spindle to adjust the grinder supported thereby'relative to its companion grinder, and a motor for rotating said spindle, said motor having the armature thereof secured to said spin dle for vertical movement therewith and having a stationary field in which said armature is moved when said spindle is adjusted vertically.

2. A grinding mill comprising a vertical between said grinder and motor to interoe t moisture or other substances which t fall from said grinder onto said motor.

4. A mill compri'sin a rotatable grinder, an upright shaft for iving said grinder means for collecting material dischar from said grinder, a motor directly connected with said shaft, packing surrounding said shaft to prevent moisture or other substance from vitatin around said shaft a cover below said collecting means and interposed between said motor and grinder.

5. A grinding mill comprising an upper and a lower grinder, an upright spindle for driving one of said ders relative to the other, a motor direct y connected w 1th and spindle beneath said grinders, surrounding said spindle, and a cover interpgsed between said stones and said motor low said pac d a loweri stationary grm' er, an upper rotary grin er, an n right spindle, a driver carried .by said spindle, removable acers inte between said spindle an said driver to adjust the position of said driver on said spindle, a support for said upper grinder carried by and driver, and means in between said support and said driver for rotating said support while 6. A mill compr sing ment of said support relative to said driver to accommodate the faces of said stones to one another.

7. A mill comprising a lower stationary grinder, an upper rotary grinder, an upri ht spindle, a driver mounted on said spindle and having a cockhead carried thereby, a bail for su porting said grinders mounted on said cockliead,-means for rotating said bail from said driver while permitting relative movement thereof, means for raising and lowering said spindle, and means for adjusting said driver relative to said spindle. p,

8. A mill having a pair of grinders arranged one above the other, a vertical spindle supporting the upper grinder, means for raising and lowering said spindle to ad just the grinder supported thereby relative to its vcompanion grinder, and a motor for rotating said spindle, said motor having the armature thereof secured to said spindle forvert'ical movement therewith and having a stationary field structure in which said armature is moved when said spindle is adjusted vertically for the purpose of adjusting the grinders.

In testimony whereof I have signed my name to this specification on this 22nd day of November A. D. 1921.

GEORGE E. CHAMBERLAIN 

